Comprehensive and Detailed Explanation:

The correct answer is B — Request SSH key authentication to be enabled for the FTP user and create an SSH Key in Key Management.

SSH Key authentication allows secure, passwordless connection to the Enhanced FTP server.

It eliminates the need for password rotation, thus avoiding manual updates every 90 days while still maintaining security.

SSH keys are managed within Marketing Cloud’s Key Management.

❌ Why others are wrong:

A: SAML SSO is for user login to Salesforce/Marketing Cloud apps, not for FTP authentication.

C: ‘Exclude FTP Users from Password Expiration’ is not available for standard Enhanced FTP users (it’s only for system user accounts under certain conditions).

D: SFTP is already in place through Enhanced FTP; the issue is not switching protocols but eliminating password dependency.

Exact Extract from Salesforce Official Documentation:

Salesforce Help — Enhanced FTP Authentication:

"To avoid password expiration impacting file transfers, request SSH Key Authentication to be enabled for the Enhanced FTP user. SSH keys allow passwordless authentication for secure automation."

(Source: https://help.salesforce.com/s/articleView?id=sf.mc_es_enhanced_ftp.htm )

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